Locking Horns

"If someone wants to lock horns with me, they need to know that I am not one to engage in a battle without a determination to win."

Well articulated. Like a good king. Or crown prince.

Kings, like dominant stags or bulls, proudly exhibit their horns. They
willingly accept every challenge to battle. They always do so with a
determination to win. Failure to win would weaken their reign. The
killing of enemies helps to establish it.